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authorRichard Weinberger <richard@nod.at>2013-08-17 18:46:00 +0200
committerRichard Weinberger <richard@nod.at>2013-09-07 10:38:34 +0200
commitf75b1b1bedfb498cc43a992ce4d7ed8df3b1e770 (patch)
treee7afc9647b9cc80fb95ee9dae7d9532b67efdc01 /arch/um/include/shared
parent65984ff9d2179a97e5a11aaef1e86fdb276cfad5 (diff)
um: Implement probe_kernel_read()
UML needs it's own probe_kernel_read() to handle kernel mode faults correctly. The implementation uses mincore() on the host side to detect whether a page is owned by the UML kernel process. This fixes also a possible crash when sysrq-t is used. Starting with 3.10 sysrq-t calls probe_kernel_read() to read details from the kernel workers. As kernel worker are completely async pointers may turn NULL while reading them. Cc: <stian@nixia.no> Cc: <tj@kernel.org> Cc: <stable@vger.kernel.org> # 3.10.x Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'arch/um/include/shared')
-rw-r--r--arch/um/include/shared/os.h1
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index 95feaa47a2fb..c70a234a3f8c 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -200,6 +200,7 @@ extern int os_unmap_memory(void *addr, int len);
extern int os_drop_memory(void *addr, int length);
extern int can_drop_memory(void);
extern void os_flush_stdout(void);
+extern int os_mincore(void *addr, unsigned long len);
/* execvp.c */
extern int execvp_noalloc(char *buf, const char *file, char *const argv[]);